Underfeed furnace.



R. S. RILEY.

UNDJJRPEED FURNACE.

APPLICATION FILED 001.220.1511.

Patented July 14, 1914 4 SHEETS-SHEET 1.

R. S. RILEY.

UNDE'RFEED FURNACE.

APPLICATION FILED OCT. 20, 1911.

1,103,625. Patented July 14, 1914.

4 SHEETSSHEET 2.

QT fi/atrzezssaa- 21, M272, Z01:

R. S. RILEY.

UNDERFBED FURNACE.

APPLICATION FILED 00120, 1911.

[fella-rotor.- K. S

R. S. RILEY.

UNDEBFEED FURNACE.

' APPLICATION FILED 00T.20, 1911. L103,625 Patented July 14,1914,

4 SHEETSSHEET 4.

ROBERT SANFORD RILEY, OF IRDVIDENCE, RHODE ISLAND.

UNDEBIEED summon.

Specification of Letters Patent.

Patented July 14:, 1914..

Application filed October 20, 1911. Serial No. 655,621.

To all whom it may concern bed and below resident of Providence,

Be it known that I, ROBERT SANFORD RILEY, a citizen of the United States, and in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Underfeed Furnaces, (Case A,) of which the following is a specification.

This invention relates to furnaces of the underfeed type, in which fuel is fed into the furnace below the surface. of the fuel the air supply for the purose of distilling the volatile constituents of the fuel and burning the same before the carbon and other solid constituents arrive at the zone of combustion and are suiticiently heated to ignite.

The principal object of the invention is to provide in a furnace of this character in combination with means for forcing the fuel into the furnace, additional positivelyacting means for eflecting a subsequent positive fecd or advance 0 the burning solids and therefuse to the part of the furnace from which the incombustible resi due is eventually removed.

Another'object is to provide for automatic breaking up of lumps of coke and clinker so that the fuel bed will be homogencous and of the desiredgdepth over all parts of the furnace, without having either lumps which burn too slowly or holes which permit wasteful escape of the air and diversion thereof from other parts of the furnace. I

Another object is to provide for automatically cutting clinker from the side walls of the furnace as rapidly as it forms thereon, and also for breaking off the clinker which has a tendency to form on the front wall of the furnace and extend over the fuel bed.

A further bed of a wide effect, a number of distinctfuel'beds, merging into one another but to some extent distinct and separate.

"Astill. further object is to construct a furnace having a 'nimber of retorts in such object as to divide the an a way that air under natural draft may enter the furnace between the retorts in addition to" the air which is supplied under forced draft to'the conduits'provided therefor.

furnace into. what 1s, m

'trated in Fig. 9.

A further object is to provide a novel construction of furnace by which the initial feed of the green fuel occurs from below the surface of the fuel bed and the air supply, and in which the final feed of the fuel, after the volatile constituents have been driven off and the carbon is ignited, occurs over surfaces between and through which a suflicient quantity of air to support combustion is admitted.

, Another object is to provide an improved form of nozzle or air outlet by the use of which the air may be delivered across the entire space between two adjacent retorts or between the sides of the retort and the walls of the furnace.

The foregoing objects are to some extent the same as those sought in other forms of furnace which constitute the subject-matter of copcnding applications filed concurrently herewith bearing the Serial Numbers 655,822 and 655,823 respectively.

The particular embodiments of the invention illustrated and described in the present application represent two ways differing somewhat in detail from each other, but containing the same essential principles by which the objects sought are attained.

In the accompanying drawings Figure 1 represents a longitudinal section of part of a furnace taken through the center of one of the retorts of the furnace. Fig. 2 is a plan view, partly in section, of two of the retorts of such a furnace. one of the retorts being shown entirely in plan and the second being partly in section on line 2-2 of Fig. 1. Fig. 3 is a longitudinal section of the air-supplying apparatus of one retort. Fig. 4: is a cross section of one of the retorts on line 4 4: of Fig. 1. Fig. 5 is a front elevation of two of the retorts of the furnace. Fig. 6 is an elevation of one of the retorts as seen from the'bridge wall of the furnace. Fig. 7 is a cross section on line 77 of Fig. 1. Fig. 8 is a cross section on line 88 of Fig. 1. Fig. 9 is-a view similar to Fig. 1, representing a modified embodiment of the invention. Fig. 10 is a longitudinal section of one of the air conduits of a retort. Fig. 11 is a plan view of two retorts of the furnace illus- Fig. 12 is a front elevation of this part of the furnace. Fig. 13 is a section on line 13-13 of Fig. 9. Fig. 14 is a section on line l t--14 of Fig. 9.

Fig. 15 is a section on line 1515 of Fig. 9. Fig. 16 is a perspective view of one of the air outlet boxes.

Referring to Figs. 1 to 8 of the drawings,l represents the front wall of a furnace inclosure, and 2 represents a bridge wall. 3 represents a wind box or air trunk extending across the furnace transversely thereof. The side walls of the furnace and the means for supporting the air trunk are not shown, since illustration thereof is not necessary to an understanding of the invention. Extending over the air trunk from the front wall toward the bridge wall are members forming the sides and bottom of a retort, or, if desired, of two or more retorts, into which the fuel is introduced and in which it 'is distilled before being ignited. The sides of the retort-shown in Figs. 1 to 8 are formed in part by two boxes or conduits placed side *by side and secured together, and in part by air emission members 11, hereinafter described. The conduits are designated by the numerals 4 and 5, and are arranged transversely of the air trunk and extend both to the front and rear thereof, resting on the trunk between their ends.

.Those parts of the conduits which rest on the air trunk are substantially horizontal, as is also the part of the trunk on which they rest, so that they are enabled to slide on the trunk from front to rear and the reverse. These parts of the conduits are open at the bottom, and in the top wall of the air trunk are registering openings which permit the air to issue from the trunk into the conduits.

The outermost walls 6 of the conduits; are substantially vertical, as shown in Figs/4, and 8, and form the outer boundaries of the entire retort structure. 7 form the sides of the retort proper, which may also be described as the channel through which the fuel is fed and in which it is distilled. The air conduits 4t and 5 are thus double-walled or hollow sides of the retort which at the same time define, the sides of the retort and conduct into the furnace the air necessary to'support combustion of the fuel. The inner wall v7 of each conduit is so shaped that it lies in contact with the corresponding wall of the adjacent conduit from the rear end and bottom of the conduits to,

a. line designated ab and to the forward end of that part which rests upon the air trunk. Above the line (1-1) the walls 7 of the two conduits diverge and form a trough. Forward of the point I) the walls of the conduits do not make contact at all, but are somewhat offset toward each other, as shown in Fig. 8, so as to form shoulders 9 underlying the edges of a plate 10 which forms the bottom or floor of the retort.

The upper sides of the conduits 4 and 5 are open throughout their entire length, that The inner walls is, there is no wall bridging the space between the side walls 6 and 7 at the upper edges of such walls. Upon these edges are The boxes have each four walls, disposed at e the top, front, and at the sides, such boxes being entirely open at the bottom and rear.' The inner and outer side walls register with the inner and outer walls of the conduits; so that each box forms,in effect, a continuation upward of the conduit. The inner side walls of the boxes have lateral openings 12 which permit the air to flow directly across the mouth of the retort. The front walls of the boxes are shorter than their open rear sides hence, when they are placed in series upon the conduits, as shown in Figs. 1 and3, a

narrow slit is left at the top of the rear side of each box extending throughout the entire width thereof. These slits direct the air toward the rear of the furnace into the-fuel which emerges from the retorts and'over flows the sides thereof. Preferably the top walls of the-air boxes are extended at the rear so as to form lips 13 overlying the boxes next adjacent at the rear to prevent. the air from rising directly from the rear outlets,

and also to prevent fuel and ash from falling between and through the boxes into the air spaces beneath them. These lips have a relatively great length in order that the boxes may have a long life before the lips are so far burned away as to be incapable of performing their described functions. The burning of the lips, however, is very cool by the fresh air continually flowing along their under surfaces. The front walls of the boxes are extended downward between the side walls of the air conduits and, provided with hooks lt'which partly surroundcrossbars 15 extending across the open upper sides of the conduits. By this means the air boxes are retained in place. The conduits are air-conducting, or air-supplying means, and the outlet boxes and bars (hereinafter described) are air emission, or air discharging means, in connection with, and continuation of, the air-supplying means.-.

slow, because they are kept comparatively I The upper edges of the conduits are given a slight slope downward from front to rear,

and the air outlet boxes 11 follow this slope. Thus the mouth of the retort, which is defined by the air boxes, is somewhat sloping. It is important to note that thisslope is less than that down which loose granular material will slide by gravity, and is generally not greater than twenty degrees from the horizontal. The bottom plate 10 of the retort is preferably arranged at a slope less, that is, more nearly horizontal, than that of the retort mouth. At the lower and rear ends of the conduits and in rear of the retort floor I provide one or more air emission members having the form, in this embodiment of the invention, of hollow iron bars 16 which extend entirely across the conduits from beneath the fuel.

from the outer wall of one to the outer wall of the other and thus cross the space between the boxes. These bars are substantially identical in cross section with the boxes 12, as shown in Fig. 4, and differ from such boxes only in that they are of greater length and that they may be provided with bottom walls 17 at their middle portions, between the openings at their ends which register with the open sides of they conduits. The air which is admitted to these bars is discharged through the wide slit between the top wall of one bar and'the top of the next bar at the rear, which slit extends across the entire width of the retort structure. The position of the bars 16 is such that the fuel which issues from the retort passes over them and they thus form grated surfaces which support the fuel during the final stages of combustion and supply air thereto The rearmost element of the retort structure is a hollow bar 18, equal in width to the combined width of the two air conduits, which is bolted to their ends and has a smooth rear wall which acts as a pusher for ash in a manner presently to be described.

The bottom of the retort, which, as

before stated, is a stationary plate, is bolted to the rear edge of a tube or fuel trough 19 which passes, under the front furnace wall and extends outside of the furnace, constituting a means for conducting fuel to the forward, or admission, end of the retort.

This tube. is provided with a bracket 20 which is secured to the air trunk. and is thus supported by the trunk. In the upper side of the tube or conduit 19, and on the outside of the furnacewall 1, is an opening 21 surrounded by a'hopper 22 for admission of fuel. A plunger or pusher 23 is mounted to reciprocatein the forward end of the tube 19 beneath this opening. A driving shaft- 24 rotates in front of the furnace and is provided with a crank 25 which is connected by a link or connecting rod 26 with the pusher 23 and somoves the 'latter back and forth. This movement of the pusher causes the fuel, which. is ordinarily coal, to be fed into the forward end of the retort. The locations of the pusher 23, the tube 19 and'the bottom '10 are such,being partly below and partly in front of the outlets through which airis discharged into the furnace, that an. underfeedof fuel is afforded, the reen fuel when in front of and'below the zone of combustion andbeing trunk is a bracket 36 carryin 137 on-which is mounted a i gradually forced across the mouth of the retort and through this zone to the surface of the fuel bed as successive quantities of fuel are fed into the retort. 1

The forward ends of the air conduits 4 and 5 are provided with plates 27, 28, which lie outside the fuel trough 19, as shown in Fig. 2. They prevent the fuel from escaping when'relative'movement between the retort walls or air c'onduits and the fuel trough occurs. Such relative movement occurs when the retort walls, including the air conduits and outlet boxes which form such walls, and excepting the bottom plate, move back and forth. For thusmoving the conduits I provide, in' the embodiment shown in Figs. 1 and 5, a lever 29 connected to the wrist pin of the connecting rod 26 and having a fulcrum upon a link 30 which is pivoted at 30 to the bracket 20. A link or connecting rod 31 is pivoted to the connecting portions of the air conduits and is engaged at its forward end with the lever 29. As such lever is oscillated in consequence of the back and forth movement of the pusher, the retort wallstare simultaneously and oppositely re ciprocated in a forwardv and backward direction, thus causing said walls to slide across the top of the air trunk 3.

Provision is made for varying the amount of travel of the retort walls according to the rate at which the fuel is to be fed and the incombustible residue of the fuel, or refuse, is to be discharged. A convenient device for readily effecting such an adjustment is that shown in Figs. 1 and 5, and it consists in making the lever 29 double, locating the link 31 between the parts of the lever so that it restson a pin 32 carried by the lever, and mounting pins 33 and 34 in the link on opposite sides of the lover. The space between the pins 33 and 34 is slightly less than the travel of the 1ever,ar'In,'so that these pins are alternately engaged by the lever and the minimum amount of motion is given to the retort walls. U-shaped shims or fillers 35 may be hung on the link between the lever and either or both of the pins 33, 3 1, to y diminish the amount of lost motion and thereby increase the travel of the retort walls,'and also to walls.

'Mounte'd upon the rear side of the a r a p1vot pin ead plate 38 whiohextends across from the bar 18 to the bridge wall. Preferably it is below the bride Wall, but such wall may have an opemng above the plate.

provided for the purpose of allowing ashes and other refuse .topass' from the dead plate,

and it'is controlled by a damper plate 39 which is so 0 nstructed' and arranged as to yield rearwar y to permit passage of the refuse through the opemng, and to cover alter the location of said Such opening is the opening and prevent fiow of therefrom when the depth of ash on the dead plate is insufiicient for that purpose. The

dead plate may be swung downward from time to time to discharge ashes into the ash pit, or it may be permanently fixed in a orizont al or slightly inclined position and a continuous and gradual discharge of ash effected. As the fuel is consumed and fed to the rearfthe refuse finally accumulates on the dead plate and is forced little by little toward the rear of the latter by the pusher 18, finally passing through the opening between thedead plate and the bridge wall, and falling into the 'ash pit. If this opening should not be large enough to admit all the ash when the dead plate is horizontal,'the latter may be inclined more or less, to em large the opening, and may be secured in such inclined position. Thus the .pusher 18 is seen to be a refuse dis osal device which is connected to the air supplying means and is operated as a part thereof to continuously displace the refuse which accumulates on the dead plate. The operation of said disposal device is automatic,as described, whereby the device constitutes an automatic dumping mechanism which limits the accumulation of ash to a predetermined amount. The means which causes the movement of the air ment 0 I e refuse disposaldevice, or pusher 18, being the fuel feeder 23 acting through the lever 29 and link 31, it is correct to consider that the fuel feeder is the actuator of the refuse disposal device'and that the le ver 29, link 31, and air conduits constitute connections through which said feeder drives or operates said device. It will be seen by comparing the lengths of the arms .of thelever on each side of its fulcrum (the point of connection of the lever with link 30) that the movement of the refuse dis: osal" device is less'than that of the fuel eeder. Such movement may bemade still less by removing one or more of the shims or fillers to permita greater or less amount of lost motion between the lever and the connections by which the movement of the lever is transmittedto .the disposal device. Herein resides an exceedly important feature of the invention, fdifiiy this means the rate of dumpin of the refuse may be regulated to a rate w 'ch is in the same proportion to the rate of admission of fresh fuel as the proportion of incombustible matter in the fuel to the whole amount of fuel. Thus. when the percentage of. refuse in the fuel is known, the lost mqtionconnections may be set to give the disposal device such an extent of reciprocatory movement that its volume of displacement bears'substantially the same proportional relation to the volume v of displacement of the feeder, due

'65 to its reciprocatory movement, as of the g means, and thereby the move-' incombustible refuse bears to the total amount of fuel fed into the retort. In this way, the ash is dumped into the ash pit as fast as it accumulates, in an entirely automatic manner, without necessity ofa periodical dumping of the dead plate, and so without varying the amount of ash which remains constantly upon the dead plate. That is, the constant dumping here described'takes place entirely at the rear edge of the dead plate and a substantially constant quantity of ash remains all'thetime on the dead plate. There is never an excessive accumulation of ash on the dead plate, or a complete uncovering thereof, such rasoccurs periodically in other is es of fur-' nace and has been found objectionable, except when on occasion it becomes necessary to dump the entire accumulation. After an adjustment of these connections has been made, there is no necessity for attention on the, part of the attendant unless the adjustments need to be altered for some reason, as to increase or diminish the accumulation on the dead plate, or because a diflerent kind of coal, having more or less ash, is fed into the furnace.

- The modification of the invention shown in Figs. 9 to 15 is the same in general principles as that hereinbefore described, and the parts corresponding to those already described are designated by thesa-me reference characters. The main differences between these two embodiments are that the plate which forms the retort bottom is made a part of the retort structure and reciprocates therewith instead of being stationary, and that the pusher is provided with an extension which accomplishes the function of the 1 stationary inclined plate of the form first described. In the second form the retort sides are formed of parallel air conduits 41, 51, which are bolted to a box 52 and communicate with the interior thereof. This box 52 is open atthe bottom and-overlies the air 110 trunk 3, with its opening in registry with openings in the top of the airtrnnk. A rib 54 in the box 52 rests upon a roller 55 which is supported by plates 56 in the air trunk. The rearends of the conduits 41, 51 rest upon rollers 57 which run upon rails 58 Thus the retort has a roller hearing. The fuel conduit or trough 19 is formed in the casting which constitutes the box 52 and travels therewith back and forth beneaththe hopper 22- which is independently supported by the furnace wall. The bottom of the retort is formed by a plate 59 placed in continuation of the bottom -ofthe fuel trough and secured to the box 52 and to the air conduitsAl, 51. The pusher23 has an extension 60,- lying uponthe retort bottom and. extending into the retort, provided with rising shouldersfil, 62. The shaft "which drivesthe pusher and reciprocates the retort 1,86

is designated by 63 and has bearings mounted in a bracket 64 secured to the air trunk.

An eccentric tiatlrives an eccentric rod 66 whichis pivoted to the forward end of the 4 retort, there belng as many such eccentrics 'bars 16. In the operation of this form of Y the movement of the retort walls p the furnace the underfeed of the fuel is accomplished by successive stages by the pusher 23* and the shoulders 61, 62, on the extension of such pusher. It should be observed that the forward sides of the shoulders 61, 62, are sloping. so that when such shoulders are withdrawn they tend to raise the fuel rather than to draw it backward and the fuel then falls in the rear of the shoulders, enabling them to advance it fartherinto the furnace upon the next rearward stroke. In this way the green fuel is forced into the retort beneath the surface of the fuel bed and from below the line of air openings. The subsequent overfeed of burning combustible and refuse is accomplished by the movement of the retort itself until the refuse is finally delivered upon the dead plate'38 and pushed therefrom by the ash pusher 18 as already described. I

In the stoker which I have invented and have 'just described, the function of the pusher is merely to introduce the fuel into the retort and not to clean the fire and feed the fuel onward after it has become thoroughly ignited. The latter functions are accomplished by the movement of the retort walls and the air-admitting means. The latter, in their movements toward the front of the furnace leave the fuel unsupported. so that it falls directly downward a slight distance, and on their rearward movements they feed this fuel a slight distance to the rear. .This is the case in both described forms of the invention. The movement-of the retort walls thus produces a positive feed of the burning fuel and refuse toward the lowest part of the fuel bed, which liri kthis. -1nstance is at the rear of thefurnace. The

slope of the retort mouth is so designed that uces the desired rateof feed. In this way' the feed is certain and takes place at exactly the predetermined and desired rate. :"The'com' stant agitation ,of thefuel produced by this movement causes all lumps to, be broken 'up and the fuel bed to be reduced to-a, homo-1' 'tively free flow of air between gencous condition. As the particles of fuel and refuse are all much the same size, and. moreover, are kept in continuous rearward travel. the formation of holes in the fuel bed is prevented. \Vhere so-called gravity feed is depended upon, it is found that with fuel containing nmch slag, lumps will be formed ip some parts of the furnace and holes will open in other partsof the fuel bed. The latter are extremely deleterious, since'they permit the air to escape with less resistance than at other places, so that a greater proportion of the air passes through them, chilling the boiler and diverting needed air from other parts of the furnace, which are in consequence insufficientlysupplied with air to effect the most efficient combustion. With my improved mechanism these objectionable effects cannot occur.

Another undesirable result encountered where so-called gravity feed is depended upon is the adhesion of clinker to the side and front walls of the furnace inclosure. Clinker, wherever it accumulates reflects heat upon the parts of the furnace beneath it with harmful efiect, causingsuch parts to be more rapidly burned away than they would be under normal conditions. Sometimes over the fire to choke it by obstructing the draft and the feed of fuel and thus seriously impair the efliciency of the furnace. In my improved furnace the moving retort walls and the movement of fuel positively induced by them cuts and breaks away all suchdeposits of clinker.

Each retort structure is made as a unit in proportions designed according to the results required. One or more of these retort-s, up to any number required, may be placed side by side in a furnace without necessitating any differences in design between a one-retort furnace or a multiple-retort furnace. Moreover, as the retorts are structurally independent of each other and are merely placed side by side without being connected together inan airtight manner, it is possible for air under the natural draft of the furnaceto flow between the'outer side wallsof adjacent retorts. These walls, being ordinarily of cast metal and unfinished, are necessarily so rough that a comparathem is permitted. Again, since the air-outlet slits-of the boxes 11 extend entirely across the rear sides thereof, such outlet slits are substantially equal in width to the distances between adjacent retorts or between the sides of the the cranks or eccentrics which operate adjacent -retorts are set opposite each other,

or are otherwise spaced angularly about theirnaxis so that oneretort may move 1n- 'ward while another moves outward and vice versa. Each retort with its flanking walls and grates thus independently supports its own part of the fuel bed, and in moving rearwardly, feeds this part little by little but it is, on the contrary, within the contemplation of my invention to make them as grates or otherwise adapted to let flow of air through them, and, accordingly, since the real purpose and function of such plates is to support the refuse discharged from the tort with flanking side walls -retorts, I include under the term dead plate any sort of device capable of supporting refuse.

Having thus explained the nature of my said invention and described a way of constructing and using the same, although with out attempting to set forth all the forms in which it may be made or all the modes ofits use, whatIclaimis: I

1. A furnace including a fuel-burning retort, having air conducting and discharging means at the sides and above the bottom thereof, to which air under pressure is sup-v plied, and means for, producing movements of the entire side walls and the air-conducting means longitudinally whereby to produce a feed of fuel and ash.

2. 'In a furnace, a series of substantially parallel upright walls and intermediate fuel-supporting membels, formingfuelburning retorts, sa id walls having air emission means within their upper means located near the forward ends of said retorts for propelling the fuel thereinto, and means for moving said walls, and. thereby the air emission means, to'etfect a further feed of the fuel in process of combustion, andofrefuse. w

3. In a furnace having a fuel-burning reand air-supplymg means, in combination with fuel-push- -.ing meansarrangedto propel fuel into such retort so as to effect an underfeed of fuel into the retort, said side walls and airsupplying means 'reciprocatively movable for producing a progressive feed of fuel from the retort, and mechanism connected-to said air-supplyingmeans and operative to reciprocate the same.

4.- In a furnace,a fuel-burning cluding upwardly extending sides which formed and a tosupport fuel at each side of the retort, cans for feeding fuel into said retort beneath the bed of fuel, 5

retort in (and means forproducing a movement of the sides of the retort in their entirety, including the parts of such sides which form the mouth of the retort, insuch manner as to advance the fuel and ashlongitudinally of the. furnace. J

5. In a furnace, a retort having side walls, means for introducing fuel into Said retort below the upper limits of said walls, and means for'moving the entire retort walls, including both the portions thereof which define the retort mouth .and the portions which support fuel at- ,each side ofsnch mouth in a manner such as to effect a longitudinal feed of all the fuel in the furnace.

6. In a. furnace, a retort having air-supplying means at its sides with outlets arranged to direct air across the retort, means for moving the same, means for introducing fuel into the retort, a refuse depository aran automatic refuse disposal device connected with said air-supplying means, and operated therewith for continuously displacthe refuse from said depository.

7. In a furnace, a retort'including a channel and movable air supplying means at the sides thereof having outlets arranged to direct air across such channel, and a refuse dumping mechanism connected with and-operated as a part of said airsupplying means.

8. TIn an underfeed furnace, a retort, means for feeding fuel thereinto at a point near one p positively a progression of fuel and from a level below mouth, of which the slope 1s less than cient-to permit sliding of the fuel by gravity, and the walls of saidretort being constructed to support fuel issuing from the retort and mounted with capability of movement, means for for fuel into the retort nearthe higher end ow the upper limits of the walls at such end, and mechanism for moving said walls horizontally, whereby toeflect a further feed of the fuel and refuse. a

11. a furnace, an elongated fueLburning retort having hollow sides the retort bottom and provided near the upper with openings to permit- ;10. In a furnace; a fuel-burning retort. having a slop' ranged to receive the refuse of the fuel; and

end thereof, from beneath the fuel bed at toward the i means for intro above discharge of air, said sides being mounted,

- refuse.

12. In a furnace, an elongated retort having a stationary bottom, movable sidesan'd' fuel-supporting elements rising above said bottom, means for forcing fuel into the retort, and means for moving said sides and elements relatively to the bottom and in the direction of the length of the retort, where by the fuel is forced out of the retort mouth and positively advanced.

13. In a furnace, a retort having double walled sides forming air conduits, said sides being movably mounted, means for conducting air to the interior of said double-walled sides, said side's having outlets through which the air passing thereinto may escape into the furnace, means for feedmg fuel into the retort and across the line of air outlets, and mechanism for moving said doubled-walled sides back and forth to disintegrate and feed the fuel.

14. In a furnace, a retort consisting of upright side. members and a bottom extending between such sidemembers, said side members also serving as division means between the retort and air spaces at each side of the retort, means for admitting air to said air spaces, air emission members mounted upon the upper sides of the side members and communicating with said air spaces and having discharge openings, and means for moving the side members back and forth to feed the fuel out of the retort.

15. In a furnace, a pair of conduits or air boxes arranged side by side separated from one another through a part of their extent soas to provide a fuel retort between them, said conduits having their upper boundaries sloping downwardly from front to rear and provided with provision for emission of air, a bottom plate extending between the conduits below the upper ends thereof, and above their lower ends, air discharging means at the lower ends of the conduits extending across the entire width thereof between their outer walls, said conduits and the lower air discharging means being movable in directions extending generally from front to rear, means for introducing fuel into said retort, and mechanism for moving the air conduits and air discharging means," whereby to propel the fuel in process of combustion toward the rear of the furnace.

16. In an underfeed stoker, a plurality of air conduits arranged with a space between them forming a fuel retort and having outlets for air at the upper edges. or mouth, of

the retort, said conduits being mounted with ,tiallv horizontal direction,

for forcing fuel into one en provision for horizontal back and forth reciprocation, ..means for forcing fuel into the retort between the conduits, and mechanism for reciprocating the conduits.

17. In a furnace, at retort having side walls with inclined upper limits mounted with provision for movement in ,a substanpushmg means of the retort, and mechanism for moving the retort walls relative to the retort bottom.

18. In a furnace, a retort havingwalls mounted with provision for movement in their entirety and connected together so as to be compelled to move in unison, said retort having also a bottom independent of said walls; means independent of said bottom for forcin fuel into the end of the re tort between sald walls, and means for moving the walls.

19. In a furnace,air conduits having substantially upright walls, and being separated from one another sufiiciently to provide a fuel-containing space between them in which fuel may be distllled and ignited, said couduits having longitudinal openings in their upper sides, and outlet boxes mounted on the upper sides of said conduits over the openings in the latter and having openings 1n 1 their bottoms communicating therewith, said boxes being open on the side toward one end of the conduits and closed on thetop and three other sides,the open side of each being closed bythe next adjacent box, except for a slit at the top,.an d the' side wall toward the fuel-containing space having a discharge openin i 20. l ii a furnace, air conduits having substantially upright walls, and being separated from one another sufiiciently to provide a fuel-containing space between them, said conduits having longitudinal openings in their upper sides, and outlet boxes mounted on the upper sides of said conduits over the openings in the latter and having openi-ngs in their bottoms communicating therewith, said boxes being open onthe side toward one end of the conduits and closed on the top and three other sides, the open side of each being closed by the next adjacent box, except for a slit at the top, the top being provided with a lip extending oversuch sli and over the top, of the next box. 21, In an underfeed' furnace, a retort for primary reception and distillation of fuel, havin upright walls mounted with ca ability o movement, guiding means for determining the direction of such movement, the retort havin also a bottom transverse to the directions 0 said guiding means, means for feeding fuel into the retort, mechanism for so moving the walls, and means for prevent ing said bottom from partaking of the mo- I a. furnace, a retort having a sloping mouth open toward the interior of the furnace, the walls of which, including the retort mouth, are-mounted with capability for in.

T torts in said furnace having walls distinct their len fromthe furnace walls, and the outer walls of the outermost retorts being beside the furnace side walls, and the walls of the several retorts being separately movable, and mechanism for moving said retort walls, whereby to cut slag deposits from the furnace walls and to disintegrate the fuel.

24. In a. furnace, in combination with an air trunk, 'a'retort, consisting of a floor extending across the trunk, air conduits at the opposite sides of said floor extending above the floor to form the side walls of the retort, and also extending into the furnace beyond and below the inner end of the floor, said conduits having longitudinal openings in their upper 'sidesand being'slidingly sup- }ported on, and in internal communication with, the air trunk, boxeshaving open bot toms'and discharge cutlets mounted on the conduit openings above the floor, and hollow bars mounted on the conduits transversely lthereof beyond the end of the fioor,.said bars being in communication with the conduit wopeningsand having outlets substantially coextensive with the distance between the outer boundaries of the cpnduits.

25. A furnace consisting of a plurality of retorts, each having parallel side walls provided with air-supplying means, and theside walls of each being independent of the corresponding walls of others, and movable in their entirety and iii the direction of 26. In a furnace of the class described, the combination of a fuel retort having reciprocating walls, a support for the refuse issuing from said retort, and means actuated by said walls to push the refuse 'alon and to dischargeit from said support.

27. In a furnace, a fuel retort including reciprocating walls arranged to form the sides of the retort, a refuse depository adjacent to the discharge point'of the retort receiving the refuse of the fuel, and pushers on the end of said ,walls traveling therewith over said depository so as to displace the refuse from said depository.

- 28. In afurnace, the combination of a re: tort with means for feeding fuel into the retort, of an upright wall within the'furnace forming a side of saidretort' and being movable to propel the fuel from the retort, a plate toward which the fuel is ed to receive the refuse of the fuel, and a pusher connectedto said wall and reciprocating across the plate so as to push the refuse across and from the plate. 4 l

fed by said wall and arrang 29. A furnace comprising a fuel-burning retort, "including air supplylng means at each side, said means being mounted movably and actuated to feed the fuel, a sup the residue delivered therefrom, means for port at the rear of said retort for receiving feeding the fuel through the retort, and

means connected tosaid air-supplying means beyond said retort for continuously and gradually discharging the residue from the support.

30. A furnace comprising a fuel-burning retort having air supplying means at each side movable back and forth longitudinally,

means for so moving said air-supplying means to feed the fuel, a support arranged to receive the residue from the fuel retort,

and pushingmeans connected to the airsupplying means arranged'above the plane of said support and movable with such means to discharge the residue from the support. I

31. In a furnace, separated upright walls formingthe sides of afuel burning retort, and also constituting partitions between the retort and flanking air spaces, a plate between said walls and constituting the floor of the retort. air-emission members mounted.

on said walls and having outlets to direct the air into the furnace the desired way',. and other air-emission members arranged below and m rear of the rearward termination of said plate, coextensive laterally with the retort and air spaces, and being adapted to support, and supply air to, th'e'fuel fed out of the retort, said wallsand air-emission means being movable to efiect a progressive feed of fuel andrefuse.

32. In a furnace, a retort having side walls and a bottom, fuel-supporting airemission members mounted on each said side walls, and other fuel-supporting air-emisto'rt, over which fuel issuing from the retort passes, and through which air under pressure is supplied to support combustion, and

means for moving said retort sides and airemission members so as to effect a progressive feed of fuel.

33. In a furnace,

a retort having side walls and a, bottom,

fuelsupporting airemission members mounted on each said side s1on members below and m rear of the re walls,"and other fuel-supporting'air-emis 1 sion members below and in rear ofthe retort, over which-fuel issuing tort-passes,- an

from the rethrough w ich air under 7 pressure is sup ied to support OOmbllStiOlR said walls being mounted movably an guided to move substantially horizontally and longitudinally, and mechanism for so moving said walls, and therewith the airemission means, to feed the fuel.'

34. In a furnace, separated side walls and a bottom plate, fuel-supporting air-emission members mounted on the upper edges of each side wall, bounding a fuel-containing space which forms a fuel-burning retort, and other fuel supporting air emission members below and in rear of the bottom plate, over which fuel issuing from the re-- tort passes, and through which air under pressure is supplied to support combustion, a refuse support in rear of the last-named air-emission members, over which said members are arranged to travel, and means for moving said side walls and air-emission members so as to feed the burnin fuel and refuse, and to discharge the re fu said support.

35. In a furnace, 'a retort constructed to connected to said feeding means.

'cause preliminary distillation of the 36. In a furnace, a retort constructer} to uel before ignition, means for feeding the fuel into one end of said retort beneath the ig nited fuel, means for directing air into said fore ignition, means for feeding the 'fuel into one end of said retort beneath the ignited fuel, means for directing air into said retort transversely to the path of'the fuel, a refuse disposal device arranged toreceive the refuse after it issues from the other end of said retort, and adjustable operative connections between said device and said feeding means. I

38. In a furnace of the class described, a fuel channel having inwardly facing air openings in its walls, reciprocating feeding means to introduce fuel into one end of said channel below said openings, a support to receive the refuse issuing from the other end of said channel, a reciprocating pusher arranged to travel over said support,

se from and motion reducing connections between said feeding means and pusher.

39. In a furnace, including a fuel channel and air supplying means arranged to direct air across said channel above the bottom thereof, the combination with a fuel feeder arranged to propel fuel into the channel, of a refuse disposal device movably mounted beyond the end of the channel, in the direction of fuel propulsion, and arranged to eject refuse from the furnace, and adjustable lost motionconnections through which said feeder operates said device to eject the refuse at a rate bearing a predetermined proportion to therate of fuel admission.

, 40. In a furnace of the class described, a fuel channel having inwardly facing air openings in its walls, means to feed fuel ;into one end of said channel beneath the ignited fuel and below said openings,'means toremove the refuse issuing from the other end of said channel, and means to adjust the relative extent of movement of said means in accordance with the proportion of refuse in the-fuel. a l

41. In a furnace of the class described, a fuel channel having inwardly facing air openings in its walls, means to feed fuel into one end of, said channel beneath the ignited fuel and below said openings, means to remove the refuse issuing from the other end of said channel, power-operated connections to said feeding means and power-operated connections to said removing means, such that the ratio of the displacement of the latter to the displacement of the former is substantially equal to the ratio of the amount of refuse resulting from the combustion of the fuel, to the amount offuel fed in. v

42. In a furnace, a retort including a fuel channel and air supplyin means arranged to direct air across said 0 annel, means for feeding fuel into said'retort, a refuse depository, arranged to receive the refuse of. the fuel issuing from said retort, and a refuse ejector arranged at the rear of said retort, co-extensive in width with said channel and air supply-means, movable over said depository to displace the refuse gradually from said depository, the depos torybeing arranged with capability for dis-i channel and-air supplying means arran ed to direct air laterally across sald channe a means for feeding fuel into said retort from r a point below said air supplying means, a

wall toward which the fuel is fed from the retort, a refuse depository between said r'etort and said wall arranged so that refuse from the retort may be'deposited thereon and to provide a discharge outlet between itself and said wall, and pushing means-arranged to move over said depository toward said outlet, while always remaining at a material distance therefrom, whereby to effect a constant gradual discharge of refuse therefrom without completely uncovering the depositorysaid depository being operable to dump t e entire accumulation of refuse therefrom. p

v '45. In a furnace, in combination with fuel supporting and aerating means and means for feeding fuel into the furnace below said aerating means, of a depository normally arranged to receive and support the refuse of the fuel and ada ted to be moved or operatedso as to dump t e-material supported thereon, and fuel e ecting means arranged and 'operated in a path coextensive with the Width of said aerating means to cause a continual progression of refuse across, and discharge thereof from, the depository,while maintain ing the total accumulation thereon approximately uniform. i

46. Ina furnace, the combination of a retort, provided with means to aerate the fuel therem,'means to feed fuel into said retort, a depository normally arranged to receive the refuse of the fuel from said retort, the furnace having an outlet beyond said depository in the direction of feeding, and pushing means for propelling the refuse across the depository and ejecting it therefrom, said propelling means having arange of movement less than-the normal extent of the depository, and vthe latter being displaceable in such a wa as to remove from the support all the re use in the range of movement of the pushing means. i

47 In a furnace, a retort having a channel,a bottom, air-su plyin fuel-supporting means'at the sides 0 said 0 annel and above said bottom, and an inlet at the front end, a fuel admission feeder, at one end, arranged to injec fuel intosaid inlet, a refuse depository'near the opposite or rear end of the, furnace, there being an outlet beyond said depository in the irectio'n of fuel feed, a refuse disposing device,vlocated.in rear of and below the retort bottom and cof-extensivein width with the channel and air-s11 plying means arranged to travel over said depository toward and from said. outlet,

means for reciprocating said feeder, and

connections .through which. said feeder transmits to said disposal device movements fuel at each stroke of said feeder substantially equal to the proportion of refuse in the fuel, to cause said device to displace the refuse from the depository as rapidly'as it is deposited thereon. f

48. In a furnace, a retort comprising a channel having a bottom and having'an-inlet at its forward'end, and air-supplying 'mea'ns at the sides of such channelrising above said inlet and arranged to direct a-ir laterally across the channel,l a fuel feeder located adjacent to the said inlet and movable so as to inject fuel thereinto, a refuse depository at the rear of the furnace, and a refuse usher arranged in rear of and below theottom of said channel and co-extensive in width with said channel and air-supplying means, movable back and forth to propel low the rear end of the retort and-having a width substantially equal to that of the retort, and mechanism for so moving said airsupplying means as to effect a feed 'of fuel issuing from theretort.

50. In a furnace, a retort, a means for feeding fuel longitudinally into said retort, air-supplying means extending beyond and below the rear end ofthe retort and having a width substantially equal to that of the retort, a refuse depository in rear of said air-supplying means, and mechanism for somoving said air-supplying means as to feed fuel and refuse across the same and upon the depository. a V

5f. In a furnace, a retort, means for feeding fuel longitudinally into said retort, airs'upplying means extending beyond and be-. low the rear end ofthe retort and having a width substantially equal to that of the retort, a. refuse depositor in rear of said airsupplying means, and mechanism for so moving'said air-supplying means as to feed fuel and refuse across the same and upon the depository and said air-supplying means having a ushing portion arranged to travel across said depository and operable to pro pel the refuse across and from the latter.

52. In-a furnaee', a fuel distilling retort,

means for injecting fuel into said retort at one, end thereof air-supplying ranged beyond 'aiid below the outlet of the means armoaeae retort in the direction of fuel feed, a refuse depository beyond said air-supplying means, said air-supplying means being movable over said depository, and means for so moving said air-supplying means as to effect a discharge of refuse from said depository.

53. In a furnace, a retort comprising a channel having a bottom and having an inlet at its forward end, and air supplying means at the sides of such channel rising above said inlet and arranged to direct air laterally across the channel, a fuel feeder located adjacent to the said inlet and movable so as to inject fuel thereinto, a refuse depository at the rear of the furnace, and a refuse pusher arranged in rear of and below the bottom of said channel and co-extensive in-width with said channel and air-supply ing means, mo able back and forth to propel the fuel over said depository.

1n testimony whereof I have aflixed my signature, in presence of two witnesses.

ROBERT SANFORD RILEY.

Witnesses:

ARTHUR H. BUNN. P. W. PEzzErrI. 

